[llvm] [AMDGPU] Improve detection of non-null addrspacecast operands (PR #82311)

[Matt Arsenault via llvm-commits]

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+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -mtriple=amdgcn-- -amdgpu-codegenprepare -S < %s | FileCheck -check-prefix=OPT %s
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck %s --check-prefixes=ASM,DAGISEL-ASM
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -global-isel -mcpu=gfx900 < %s | FileCheck %s --check-prefixes=ASM,GISEL-ASM
+
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arsenm wrote:

Should also have a standalone codegen test for the intrinsic. Code suggests it may support vectors, so should include some vector tests 

https://github.com/llvm/llvm-project/pull/82311